When an application required that two DTEs (or two DCEs) needed to communicate with each other, then a null modem was necessary. Null modems were commonly used for file transfer between computers, or remote operation. However, they are done so in a way that still permits Request To Send (RTS) and Clear To Send (CTS) flow control but has no actual functionality. Make and test practice cables until you get it right every time — especially before you destroy a cable you just spent 2 hours fitting. The ZY1000 supports RTCK & RCLK or adaptive clocking and has a built-in relay to power cycle the target remotely. Gigabit Ethernet uses all 4 pairs so requires the full 4 pair (8 conductor) cross configuration (shown above). If you are using Power-over-Ethernet (802.3af) then Mode A or Alternative A uses pairs 1,2 and 3,6 for both signals and power. They have been updated over the years but still contain some now long-in-the-tooth (aka legacy) stuff about crossed cables especially.
Please take the time from a busy life to ‘mail us’ (at top of screen), the webmaster (below) or info-support at zytrax. Cat5 cable manufactured to the old specification may work or it may not — you need to run some tests. This is a USB to TTL serial cable, with a FTDI FT232RL usb/serial chip embedded in the head. It has a 6-pin socket at the end with 5V power and ground, as well as RX, TX, RTS and CTS at 3V logic levels. The cable color can be anything you choose or, more likely, the vendor decides. To avoid the need for Crossed cables many vendors provided UPLINK ports on Hubs or Switches — these were specially designed to allow the use of a STRAIGHT cable when connecting back-to-back Hubs or Switches. Documents may be found at the IEEE site.
Transport Does it support the kind of communication that you need? Info on Shielded Twisted Pair (STP) cabling. UTP comes in two forms SOLID or STRANDED. SOLID refers to the fact that each internal conductor is made up of a single (solid!) wire, STRANDED means that each conductor is made up of multiple smaller wires. Rev A5 will ship with the USB cable.